System and method for monitoring inefficient flow rates using magnetic sensor in a liquid-flow distribution system

ABSTRACT

A system and method for monitoring inefficient flow rates in a liquid-flow distribution system, such as that which is used in agricultural liquid application equipment. This may include blockages or punctures in a liquid line. The system generally includes a plurality of gauges for monitoring the supply line flow rate in a liquid application system which are monitored by a number of sensors. Immediate feedback is presented to the operator of the vehicle inside the cab. The system alerts the operator when a blockage, loss, or increase of flow rate has occurred in one of the liquid lines. The system may merely indicate that one of the lines is blocked, or the system may be more sophisticated such that it can indicate which line is blocked and adjust the flow in that line in an attempt to clear the blockage.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims priority in U.S. patentapplication Ser. No. 13/941,167, filed Jul. 12, 2013, now U.S. Pat. No.8,839,681, issued Sep. 23, 2014, which claims priority in U.S.Provisional Patent Application Ser. No. 61/719,294, filed Oct. 26, 2012,which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to liquid flow controls andmonitoring, and in particular to a blockage monitor for liquidapplication equipment, such as sprayers used for agricultural andrelated applications.

2. Description of the Related Art

Monitoring liquid flow is an important function in various equipment fordispensing, spraying and applying liquid material. For example,agricultural operations commonly involve applying liquid fertilizer,insecticide and herbicide. As an example, agricultural sprayingequipment is typically configured for liquid applications over multiplerows per pass. The equipment is commonly configured for applying liquidon eight or more rows simultaneously. Some examples of multi-rowequipment include: planters, applicators, cultivators, coulters, etc.

Row crops, which account for a large portion of overall agriculturalproduction, typically require several field operations with differenttypes of equipment. These can include tilling, planting, fertilizing andharvesting operations. Moreover, crop yields often benefit from theapplication of herbicides, insecticides and pesticides. Liquidapplication operations are conducted to maximize uniform coverage whileminimizing waste, overlap and equipment fuel consumption. Suchobjectives can be achieved by, for example, efficiently guiding theequipment in evenly-spaced, parallel passes in either straight-line orcontour guidance modes of operation. Optimum, uniform crop yields tendto result from even liquid application coverage and precise equipmentguidance and control procedures.

Liquid application equipment, such as agricultural sprayers, may besusceptible to liquid flow blockage and restriction from varioussources. For example, debris from the fluid reservoirs, such as liquidapplicator tanks, can become lodged in fluid outlets and other dischargecomponents. In many agricultural tractor-liquid applicatorconfigurations, the liquid applicators are located some distance behindthe operators. The operators are thus unable to directly observe theoperation of the liquid applicators while driving the equipment.Consequently, individual, blocked liquid lines and applicators are oftenundetected by the equipment operators, with resultant gaps in thematerial application. Uniform material application and ultimately cropyields can be compromised by liquid application coverage gaps.

Automated agricultural operations commonly use information managementvia the Internet for purposes of monitoring, reporting and controllingvarious aspects of agricultural operations. For example, liquid chemicalapplications are often documented for billing and record-keepingpurposes. Accurate records of operations are useful to operators andowners in connection with monitoring crop yields based on chemicalapplications, record-keeping, billing and other information managementaspects. Accurate records of agricultural chemical applications arecommonly useful for purposes of insuring consistent flow rates formaximizing crop yields.

Visual flow blockage monitors have previously been installed inagricultural liquid application equipment. For example, CDS-John BlueCorporation of Huntsville, Ala. manufacturers and markets the VisaGageline of liquid application flow monitors, which utilize transparentcolumns each associated with an individual liquid applicator fluidoutlet in a multi-row liquid applicator. Operators can visually observeindicator ball locations and thereby detect blocked liquid applicatorlines when the flow rate responsive balls drop below threshold operatinglevels. Such visual indicator systems tend to be highly reliable, evenunder adverse operating conditions because they rely on only one movingpart, the flow rate level indicator ball, and because operators canreliably observe the ball locations associated with multiple liquidapplicators and thus quickly discern the inoperative condition of anyparticular liquid applicator.

Although such visual liquid application monitoring procedures have beensuccessfully used for a number of years, visual observation proceduresperformed by individuals can be enhanced and improved by combining suchflow indicators with automated, electronic sensing equipment fortracking the individual fluid outlet operations.

Heretofore there has not been available a flow monitor system and methodwith the features of the present invention. These include automatedmonitoring of individual fluid outlets; operation under various lightingand visibility conditions; “heads-up” display monitoring by equipmentoperators; and operation reporting capabilities via Internet,cloud-based utilities and other automated functions.

SUMMARY OF THE INVENTION

The present invention relates to a system and method for monitoring forblockages in a liquid-flow system, such as an agricultural liquidapplicator. The system generally includes a plurality of gauges formonitoring the supply line flow rate in a liquid applicator system whichare monitored by a number of sensors. Immediate feedback is presented tothe operator of the agricultural vehicle inside the cab. The systemalerts the operator when a blockage or loss of flow rate has occurred inone of the liquid lines. The system may merely indicate that one of thelines is blocked, or the system may be more sophisticated such that itcan indicate which line is blocked.

A typical liquid applicator set-up includes a “right” side and a “left”side array of fluid outlets. Each applicator requires a supply line froma pump or a flow-divider element. The present invention is placedbetween the pump or the flow-divider and the liquid applicator. Thepresent invention includes a gauge with a number of pre-determinedlevels. The gauge monitors the flow rate as the liquid is dispensedthrough the supply lines to the applicators. If a drop in flow occurswithin a supply line, such as could be caused by a blockage within theline, the vehicle operator is immediately notified of the flow drop.Generally, a higher flow level reading indicates a higher fluid flowrate through the system. Depending on the application of chemicals orfertilizers, the operator may desire a higher or a lower flow rate,thereby requiring a higher or lower flow within the gauges. The“threshold” flow level, which is decided and set by the operator using auser interface device within the vehicle cab, depends upon this flowrate.

The operator can adjust the level of sensitivity of the system on thefly, depending on the level of flow required to adequately dispense theliquid contained within the storage tank. The flow level is monitored bya number of sensors which monitor the level of a ball within each gauge.As the flow rises within the gauge, the ball should rise. The systemmonitors the ball level and reports to the operator when the ball hasdropped to a pre-determined threshold level.

Similarly, in the event of a broken or punctured line, the result may betoo much flow through the liquid flow monitoring system. In such asituation, the indicator ball would float very high or even to the topof the flow gauge. The present invention would also be able to determinesuch a situation and alert the user to the problem.

The present invention provides a less invasive means for monitoringliquid flow blockage within an agricultural liquid applicator system.The use of magnetic field sensors/Hall-Effect sensors to sense the levelof a magnetized ball within a flow gauge is less susceptible to fluidcontamination problems as compared with flow meters, pressure gauges, orother devices.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings constitute a part of this specification and includeexemplary embodiments of the present invention illustrating variousobjects and features thereof.

FIG. 1 is an isometric view of an embodiment of the present inventionemployed in a typical environment including an agricultural liquidapplicator.

FIG. 2 is an exploded-isometric view of an embodiment of the presentinvention.

FIG. 3 is a detailed isometric view of a printed circuit board andsensor array taken about the circle 3 in FIG. 2.

FIG. 4A is a front elevational view of a flow gauge monitor elementemployed in an embodiment of the present invention.

FIG. 4B is a rear elevational view of a flow gauge monitor elementemployed in an embodiment of the present invention.

FIG. 5A is a cross-sectional view of a flow gauge monitor elementemployed in an embodiment of the present invention taken about thesectional line A-A of FIG. 4A.

FIG. 5B is a detailed cross-sectional view taken about the circle ofFIG. 5A.

FIG. 5C is an elevational view of the indicator ball element of FIGS. 5Aand 5B.

FIG. 6A is an elevational view of a first half of a level-indicatingball.

FIG. 6B is a plan view of a first half of a level-indicating ball.

FIG. 6C is a plan view of a second half of a level-indicating ball.

FIG. 6D is a cross-sectional view of a first half of a level-indicatingball as taken about the section line B-B of FIG. 6B.

FIG. 6E is an elevational view of a first half of an alternativeembodiment level-indicating ball.

FIG. 6F is a plan view of a first half of an alternative embodimentlevel-indicating ball.

FIG. 6G is a plan view of a second half of an alternative embodimentlevel-indicating ball.

FIG. 6H is a cross-sectional view of a first half of an alternativeembodiment level-indicating ball as taken about the section line C-C ofFIG. 6F.

FIG. 7 is a front elevational view of a mounting stand employed in anembodiment of the present invention.

FIG. 8 is a front elevational view of a mounting stand including aplurality of flow gauge monitor elements employed in an embodiment ofthe present invention.

FIG. 9 is a schematic diagram of a system embodying an aspect of thepresent invention.

FIG. 10 is a box-diagram schematic of a system embodying an aspect ofthe present invention.

FIG. 11 is a box-diagram schematic of a system embodying an aspect ofthe present invention pertaining specifically to the interaction betweena plurality of sensor elements and a display device.

FIG. 12 is a wiring schematic diagram for a display device for use in anembodiment of the present invention.

FIG. 13 is a wiring schematic diagram for a sensor device array for usein an embodiment of the present invention.

FIG. 14 is a flow chart showing a number of steps representing thevarious system states of an embodiment of the present invention.

FIG. 15 is a flow chart demonstrating the steps taken during theoperation of an embodiment of the present invention.

FIG. 16 is a box-diagram schematic of an alternative embodiment of thepresent invention pertaining specifically to the interaction between aplurality of sensor elements and an alternative display device.

FIG. 17 is a box-diagram schematic of a system embodying an aspect of analternative embodiment of the present invention.

FIG. 18 is a box-diagram schematic of a system embodying an aspect of analternative embodiment of the present invention pertaining specificallyto the interaction between a plurality of sensor elements and a displaydevice.

FIG. 19 is a wiring schematic diagram for a sensor device array for usein an alternative embodiment of the present invention.

FIG. 20 is a box-diagram schematic of an alternative embodiment of thepresent invention pertaining specifically to the interaction between aplurality of sensor elements and a display device.

FIG. 21 is a flow chart demonstrating a method of practicing anembodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

I. Introduction and Environment

As required, detailed aspects of the present invention are disclosedherein; however, it is to be understood that the disclosed aspects aremerely exemplary of the invention, which may be embodied in variousforms. Therefore, specific structural and functional details disclosedherein are not to be interpreted as limiting, but merely as a basis forthe claims and as a representative basis for teaching one skilled in theart how to variously employ the present invention in virtually anyappropriately detailed structure.

Certain terminology will be used in the following description forconvenience in reference only and will not be limiting. For example, up,down, front, back, right and left refer to the invention as orientatedin the view being referred to. The words, “inwardly” and “outwardly”refer to directions toward and away from, respectively, the geometriccenter of the aspect being described and designated parts thereof.Forwardly and rearwardly are generally in reference to the direction oftravel, if appropriate. Said terminology will include the wordsspecifically mentioned, derivatives thereof and words of similarmeaning.

The scope of the present invention is to implement a liquid flowmonitoring system 2 capable of notifying the user of blockages within aliquid applicator distribution run. The liquid flow monitoring system 2will pair sensing components with flow monitor gauges 4. Each gauge willcontain a magnetic level indicator ball 34 which moves vertically inproportion to the flow rate of the respective run. These balls will beelectronically monitored and used to report abnormal flow through eachliquid applicator run.

II. Preferred Embodiment or Aspect Liquid Flow Blockage MonitoringSystem 2

An embodiment of a liquid flow blockage monitoring system 2 for use inan agricultural liquid applicator is presented. The monitoring system 2provides a customizable, automated method of monitoring the flow rate ina number of liquid applicator lines 7 in an agricultural liquidapplicator system. As shown in FIG. 1, the system includes aninteractive user display 12 located in a vehicle 8 cab. The displayallows the operator of the vehicle to set a minimum flow rate thresholdand monitor the flow rate in each liquid applicator line, and alerts theoperator when the flow rate in one of these lines drops below the setthreshold.

A typical set-up employs an agricultural vehicle 8, such as a tractor,towing an implement 10 including a liquid applicator tank 6, a number ofliquid applicators 9, and liquid lines 7 which move liquid stored in thetank to the applicators. The liquid may be divided prior to entering theflow gauges 4 using a flow divider 16, and may also pass through a flowmeter 14 which ensures the proper flow rate to the liquid applicators 9.During operation, the lines or applicators can become blocked withdebris, thereby partially or completely interrupting the applicationfrom one or more liquid applicators.

Previous systems have been used to alert the operator that a block hasoccurred in a liquid line. One such system, which can be employedalong-side the present invention, is the VisaGage II Liquid Flow RateMonitor by CDS-John Blue Company, a division of Advanced SystemTechnology, of Huntsville, Ala. These previous systems require that theoperator has a clear visual path to the gauges to determine if flow hasdropped in one of the lines due to blockage. This also requires theoperator to take his eyes off of the current driving path just to verifythat the liquid applicator lines are clear.

Typical visual flow blockage monitoring devices allow liquid to flowthrough the visual gage, indicating to the operator visually whether ablockage has occurred or not. Depending on the system, each gauge mayinclude a bottom inlet 30 to accept divided flow through each gauge, orthe gauges may be joined together via a common inlet 23 runningperpendicular to the gauges, wherein the flow is not divided until itreaches the gauges.

The present invention employs visual gauges 4, such as the VisaGage II,mounted to the liquid applicator implement 10 via a mounting rack 11using mounting bolts 19 fed through a mounting plate 24 on the gauge 4.As shown in more detail at FIGS. 4 and 5, the typical visual gaugesemploy a ball 34 suspended within a housing 26. The liquid being appliedto a field is fed through the housing 26, either via a bottom inlet 30or a common perpendicular inlet 23, and is fed to the liquid applicatorline 7 via a top outlet 28. Indicator markings 32 along the surface ofthe housing 26 give the operator a visual check of where the ball 34 issuspended within the gauge 4. If a blockage has occurred, the ball willdrop to a lower level within the gauge, indicating the blockage to theoperator.

FIG. 2 demonstrates the typical construction of a sensor system node 60for monitoring flow rate blockage in a liquid applicator system. Thesensor system includes a housing 21 which contains a printed circuitboard (PCB) 18 and a gasket 17. It is ideal that the housing bewater-tight because of the nature of agricultural spraying and otherliquid application systems. Liquid entering the housing could damage thesensitive electronic circuitry. A number of sensor arrays 20 are mountedto the PCB 18. The housing is adapted to be mounted to an array 56 offlow gauges 4, such as the visual flow gauges discussed above, via anumber of mounting bolts 19. A typical set-up employs a set of four flowgauges 4 connected into an array. An ideal sensor system would adapt toone series of four flow gauges; however, a system could employ a singlegauge 4 and a single sensor system if desired. Any number of gauges andsensor arrays 20 could theoretically be used.

The sensor system housing 21 ideally includes a pair of clips 27 adaptedfor interlocking with an adjacent sensor system housing via a pair ofoffset bolt connectors 29. As shown in FIG. 2, the offset boltconnectors 29 are also adapted to be fit into one set of bolt acceptingholes 25 located in one of the interlocked gauges 4.

FIG. 3 demonstrates the sensor array 20 mounted to the PCB 18 in moredetail. In a preferred embodiment, seven sensors 20.1, 20.2, 20.3, 20.4,20.5, 20.6, and 20.7 are used to measure seven levels within the gauge4. A multiplexed Hall-Effect sensor array, as shown, is the preferredmethod of measuring the level of a magnetized ball 34 located within thegauge housing 26. A Hall-Effect sensor is ideal for the preferredembodiment of the present invention because they are used primarily forproximity or positioning detection. When using a visual gauge such asdefined and described above, the position of each sensor 20.1-20.7 inthe array corresponds to an indicator marking 32 located on the housing26 of the gauge 4. Thus if the magnetized ball 34 is at visual markingnumber six, the sixth sensor 20.6 would measure the ball's position andreport it to the monitoring system. The surrounding sensors 20.7 and20.5 would also likely receive some indication of the ball's position,though the signal would be faint in comparison. The measurement of allthree sensors would produce a precise report of the ball's 34 positionto the display device 12.

FIGS. 4A and 4B provide elevational views, and FIG. 5A provides asection of a gauge 4 showing the sensor array housing 21 between thegauge and a pair of mounting plates 36. The position of each sensor inthe sensor array is more clearly visualized here. It should be notedthat additional or fewer sensors could be used, resulting in a differentnumber of position levels. It should also be noted that in a preferredembodiment, the upper most sensor 20.7 is used to error check the sixthlevel in the monitoring system. Typically only six levels of the ball'sposition will be monitored, however the seventh sensor is used toconfirm the ball's 34 position should it rise above the sixth level.

FIGS. 6A-6D show a first type of level-indicating ball 34. This ball isconstructed by placing two halves together. Protrusions 35 are used asnecessary to provide a leak-free seal between the two halves. Magnetsare inserted into recesses 33 located internally once the ball 34 halvesare placed together and welded or otherwise joined. One issue with thisparticular construction is that the magnets may align their poles with aneighboring magnetized ball, which prevents the strongest portion of themagnetic field from facing the sensor 20. Also, if the attractionbetween neighboring ball magnets becomes lost, the ball orientationbecomes unpredictable.

FIGS. 6E-6H, along with FIGS. 5A-5C, show a second, alternativelevel-indicating ball 134 aimed at addressing the issues mentionedabove. Multiple magnets are inserted into multiple recesses 133. Again,protrusions 135 are used as necessary to produce a leak-free sealbetween the two ball halves. With the arrangement shown, the magnetpoles may be aimed directly at the sensors 20, which produces a strongerreading. The tail 136 portion of the ball 134 maintains a verticalorientation of the ball when suspended within the gauge body 26,ensuring correct magnet orientation relative to the sensor 20. The tail136 may be hollow (as shown) to promote buoyancy, but does notnecessarily have to be hollow. Even in the event that the magneticalignment between neighboring balls is “broken,” the tail will maintainthe vertical orientation, and the presence of four perpendicularmagnetic poles will excite the sensor 20. FIG. 5C indicates the ballbeing suspended within the housing 26 while water flow is travelingthrough the housing in the direction of the arrows shown.

Another possibility would be to add a guiding rod or feature inside ofthe gauge body 26 to control the ball orientation. However, this is notideal because particulates from fertilizer could become lodged betweenthe rod and the ball causing it to jam. The design described above isthe more desirable because there are fewer interacting parts and fewerfailure modes.

FIG. 7 shows a typical mounting rack 11 which could be mounted to aliquid applicator implement 10 via a pair of mounting legs 38. Themounting rack 11 includes two mounting plates 36 with a plurality ofbolt holes 40 for accepting mounting bolts 19. These correspond to themounting bolt holes 25 of the flow rate gauges 4.

FIG. 8 shows an array of flow rate gauges 4 mounted to the mounting rack11 of FIG. 7. FIG. 8, unlike FIGS. 2-5, shows visual flow rate gauges 4connected via a common liquid input line 22 running perpendicular to thegauge housings 26. Liquid enters the system through an input port 44 andflows through the input line 22, at which point it enters the flow gaugehousings 26 and exits through the upper outlets 28 and proceeds to theliquid applicators 9 via the liquid lines 7. The gauges 4 may bemechanically snapped together as shown, as is a feature of the VisaGageII visual flow gauge discussed above. A ball storage unit 42 may besimilarly mechanically connected to one or both ends of the array ofgauges 4.

FIG. 9 shows a general diagram of the liquid application system asemployed in a preferred embodiment of the flow rate monitoring system 2.A tank 6 stores the liquid which is to be applied to a field via thevarious liquid applicators 9. The liquid flows through a strainer 48which ideally removes any debris which could block a liquid line 7 orapplicator 9. A pump 52 powered by a motor 50 operates to move theliquid throughout the entire system. An optional agitator valve 46 maybe attached to the system to ensure that the liquid stored in the tankflows freely.

The liquid passes through a flow meter 14 which measures the flow rateand ensures that the rate is optimal for the liquid being applied. Anoptional flow divider 16 can be used to separate the flow of the liquidprior to sending the liquid through the array of flow gauges 4. Finally,check valves 54 are placed in the line prior to the liquid reaching theliquid applicators.

FIG. 10 shows a general box diagram of a typical set-up employing threesets 56 or arrays of four flow gauges 4 mounted on either side of theliquid applicator implement 10. As shown, three sets 56 are mounted toeach of the left and right sides of the liquid applicator, respectively.Each set 56 is electronically wired to the adjacent set of gauges, andeach side is separately wired to the user interface 12. The userinterface is triggered if any gauge 4 within any array 56 is triggered,thereby indicated to the operator that a blockage has occurred either onthe right side or the left side of the liquid applicator.

FIG. 11 provides a basic example of how the gauge and sensor system nodeassemblies 60, as shown in detail at FIG. 2, communicate with a userinterface 12. FIG. 11 demonstrates a system whereby a standardcontroller area network (CAN) bus 74 electrically communicates thesignals from the sensor system node assemblies 60 to the user interface12. The display 12 includes a plurality of level indicator lightemitting diodes (LEDs) 62 corresponding to the ball 34 level with thegauge housing 26. A separate “blocked” status LED 66 can be provided toindicate that a sensor has indicated a blockage within one or more ofthe liquid lines. A separate “normal” status LED 68 may be included toindicate when all of the liquid lines are flowing normally. A pushbutton 64 allows the operator to set the threshold level for the systemto return a “blocked” or “normal” status output. The operator can pressand hold the push button to change the threshold level, which isindicated to the operator by the level LEDs 62 lighting up to indicate aparticular level. The level LEDs 62 may also light up to indicate atwhat level the ball 34 in each flow gauge 4 is currently.

FIG. 12 is a wiring diagram for a user interface 12 display. At the coreof the display is a microprocessor 80, such as an 8-bit Atmel ATmegaseries processor manufactured by Atmel Corporation of San Jose, Calif.The microprocessor includes mounted software for handling the variouscommands received from the sensor nodes 60 and the push button 64. Thismicroprocessor receives signal commands from the various sensor nodes 60and reports information to the operator via the status LEDs 66, 68 andlevel LEDs 62. An optional piezo buzzer 85 may provide additionalinformation to the operator via an audible noise when a “blocked” statusis received. The push button 64 is also connected to the microprocessor,which then adjusts the threshold level as the operator pushes and holdsdown the button. A programming header 84 is connected to themicroprocessor 80. The processor is also connected to an externalconnector 82. Power circuitry 88 is included to handle power to thedisplay wiring circuit.

The microprocessor software code base is responsible for monitoring dataprovided by the sensor modules within the system and presenting systemstatus to the user. The microprocessor software is not based on a highlevel operating system but will instead use a cyclic executive real-timescheduler to keep precise timing of task execution with low overhead.Listed below are the primary components of the microprocessor softwareand their responsibilities:

-   -   Bootloader: Provides ability to write an updated application to        the internal flash and load the application from flash and        execute it.    -   Scheduler: Manages the execution and timing of all tasks.    -   Flow Metric Processor: Performs flow analysis calculations and        filtering based on raw sensor data.    -   CAN Message Processor: Filters and processes incoming messages        from the CAN bus 74.    -   User Interface Processor: Accepts inputs from the user and        drives visual and audible indicators based on system status.    -   Tasks: Schedulable items of the system that represent an        execution path of code that will be run for a defined interval.        -   CAN Receiver Processing        -   Audible Alarm Update        -   Visual Alarm Update    -   Services: Implement logic that uses a component or driver to        produce a desired behavior.        -   Scheduler        -   Configuration    -   Components: Represent hardware devices external to the        microprocessor. Their implementations are specific to the part        number they are designed for and make use of one or more drivers        to interface with the microprocessor/peripherals.        -   LEDs 62, 66, 68        -   Piezo buzzer 85        -   Detection Level Select 64 button    -   Drivers: Responsible for configuration and interface with the        microprocessor and peripherals. Their implementations are        specific to the hardware architecture and microprocessor family.        -   CAN        -   Timer

FIG. 13 is a wiring diagram for a gauge sensor node 60. A separatemicroprocessor 81 powers the sensor node wiring system. Themicroprocessor includes mounted software for handling the variouscommands and signals received from the sensor arrays 20. Each sensor row98.1, 98.2, 98.3, 98.4 is connected to a switch 96.1, 96.2, 96.3, 96.4,respectively. The switches 96.1-96.4 select the sensor column arrays98.1-98.4, and sensor column array selection is performed by themicroprocessor 81 which uses general purpose input/output (GPIO) forround-robin sampling. The switches should be similar to the CD74HC LogicSwitch manufactured by Texas Instruments Inc. of Dallas, Tex. Theswitches transfer analog signals from the sensors through a signal amp94. The signal amp converts the analog signals to digital, and theseanalog-to-digital signals are reported to the microprocessor 81. Rowstatus LEDs 90 may be connected to the microprocessor, which can providethe status of each row of sensors 20 to the operator. A programmingheader 87 is connected to the microprocessor 81. The processor is alsoconnected to an external connector 83. Power circuitry 89 is included tohandle power to the display wiring circuit.

The microprocessor 81 code base is responsible for processing dataprovided by the magnetic field sensors/Hall-Effect sensors as well asCAN bus communication with other modules within the system. Themicroprocessor software is not based on a high level operating systembut will instead use a cyclic executive real-time scheduler to keepprecise timing of task execution with low overhead. Listed below are theprimary components of the microprocessor software and theirresponsibilities:

-   -   Bootloader: Provides ability to write an updated application to        the internal flash via the CAN communications link and load the        application from flash and execute it.    -   Scheduler: Manages the execution and timing of all tasks.    -   Analog-to-Digital Converter (ADC) Processor: Manages the        selection and digital conversion of sensor columns and stores        this raw data in random access memory (RAM) for processing.    -   Flow Metric Processor: Performs flow analysis calculations and        filtering based on raw sensor data.    -   CAN Message Processor: Filters and processes incoming and        outgoing messages from the CAN bus.    -   CAN Metric Transmission: Aggregates the blockage and flow rate        status of all sensor columns into a message sent over the CAN        interface.    -   Tasks: Schedulable items of the system that represent an        execution path of code that will be run for a defined interval.        -   ADC Sensor Sampling        -   Flow Analysis        -   CAN data packaging        -   CAN Transmitter        -   CAN Receiver Processing    -   Services: Implement logic that uses a component or driver to        produce a desired behavior.        -   Scheduler        -   Configuration    -   Components: Represent hardware devices external to the        microprocessor. Their implementations are specific to the part        number they are designed for and make use of one or more drivers        to interface with the microprocessor/peripherals.        -   LED        -   Hall-Effect Sensors        -   Row Selection Switches        -   Analog Signal Amplifier    -   Drivers: Responsible for configuration and interface with the        microprocessor and peripherals. Their implementations are        specific to the hardware architecture and microprocessor family.        -   CAN        -   ADC        -   Digital-to-Analog Converter (DAC)        -   Timer        -   GPIO

FIG. 14 is a flow chart showing a system state diagram for the liquidflow sensor system 2 detecting a “blocked” versus a “not-blocked” state.The system is powered on and a self test state is performed at 102. Thistests the audible alarm and the visual indicators of the user interface12, such as the various LEDs and the audible alarm, which are both setto “on.” This step occurs for a predetermined number of seconds.

Next the initial flow state is set to “blocked” at 104. The audiblealarm is turned off, but the visual LEDs indicate the rows as “blocked”for any row below the preset threshold level (one through six). However,it may be necessary to include at least one row above the threshold toreach this state. Otherwise the system assumes the pump is off. Thesystem debounces at 106 for a predetermined time limit, and then anormal state is initiated at 108, wherein the audible alarm and visualindicators both register as “not-blocked.”

Again, the system debounces at 106 until a blocked state is determinedat 114. The audible alarm and blocked rows both indicated “blocked,” butnon-blocked rows remain visually indicated as “not blocked.” The systemdebounces at 106 again until a normal state is again detected at 108.This would occur if the blockage is removed manually or if the thresholdlevel is lowered by the operator via the user interface.

If all rows are below the set threshold, a “no-flow state” is initiatedat 112. The audible alarm is turned off, but the blocked rows arevisually indicated as “blocked.” Non-blocked rows, if any, would bevisually indicated as “not blocked.” This occurs until any row is raisedabove the “blocked” threshold, at which time the “normal state” is againentered into.

A system error state exists at 100 if the sensor system or userinterface detects an error. This may occur at any time due to anelectrical error or a mechanical failure within the system. Both theaudible alarm and visual indicators register as “error” at this step.For example, at start-up, the system detects that the magnetic fielddetected by each sensor 20 in a row is below a specified threshold. Thishelps to determine whether there is a magnet installed in thatparticular row. If none is detected, that row's LED is turned off and itis ignored for blockage reporting purposes.

FIG. 15 is a flow chart of the steps the flow monitoring system 2employs during a typical operation. After the system is powered on, aself test state is performed at 116. This tests the audible alarm andthe visual indicators of the user interface 12, such as the variousLEDs.

Next the initial status of the sensors is set to “blocked” at 118. Thesystem starts in the “blocked” status to allow the system to self-reportthat everything is running correctly. The other option would be toassume that all subsystems are running correctly until the systemnotifies the operator of a problem. Each separate gauge 4 is indicatedas “blocked” prior to initializing the liquid application system. If agauge does not show “blocked,” the operator should be alerted that anerror has occurred within the sensor system.

The system then checks to determine whether the pump 52 has been poweredat 120. This check continues until the system determines that the pumphas been powered, which is determined by reading the position of theballs 34 within the gauges 4. If the ball is at a point greater than orequal to one level above the “blocked” threshold, the system assumes thepump is running. The system proceeds to monitor the sensors. At 122, theaudible alarm should turn off and indicate “not blocked,” and the visualindicators should indicate the same.

A check is performed at 124 to determine whether all of the runs areshowing a “blocked” result. If yes, at 126 the audible alarm shouldindicate a “not-blocked” or “ready” status, the visual indicators of theblocked liquid lines should indicate a “blocked” status, and the visualindicators for the non-blocked liquid lines should indicate a“non-blocked” or “ready” status.

A check is performed at 128 to determine whether any runs are showing as“blocked.” If yes, at 132 the audible alarm should indicate “blocked”status, the visual indicators of the blocked liquid lines shouldindicate a “blocked” status, and the visual indicators for thenon-blocked liquid lines should indicate a “non-blocked” or “ready”status.

If at 128 no liquid lines are indicated as blocked, then at 130 theaudible alarm should indicate a “not-blocked” status, and all visualindicators should indicate a “not-blocked” status. This series of stepscontinues until the pump is shut off and the monitoring system ispowered off.

III. Alternative Embodiment Flow Blockage Sensor System 202

FIG. 16 shows a basic connection diagram for connecting a number ofgauge and sensor node assemblies 210 to a display device 212 via acommunications bus 214. This presents an alternative connection andcommunications set-up from a similar design shown in FIG. 11. Thedisplay device 212 shows an alternative arrangement of elements,including level LEDs 62, “blocked” status LED 66, and a push button 64.

IV. Alternative Embodiment Flow Blockage Sensor System 252

In an alternative embodiment flow blockage sensor system 252, much ofthe system architecture remains the same as described above. However,new technology can be utilized to provide additional information andenhanced options to an operator. In such a system, a wireless tabletcomputer, such as the iPad® manufactured by Apple, Inc. of Cupertino,Calif., is provided to the vehicle operator. This table computeroperates as a smart user interface 262 which, unlike the user interfacedescribed above, can provide the operator with the status of each andevery flow gauge 4 in the liquid applicator system. The operator canalso set a separate threshold level for each gauge using the interface.

FIG. 17 shows a general box diagram of a typical set-up of thisalternative embodiment system employing three sets 256 or arrays of fourflow gauges 4 mounted on either side of the liquid applicator implement10. As shown, three sets 256 are mounted to each of the left and rightsides of the liquid applicator, respectively. Each set 256 iselectronically wired to the adjacent set of gauges, and each side isseparately wired to an ECU gateway 266 which provides a wirelessconnection 264 to the user interface 262 display device. The userinterface is triggered if any gauge 4 within any array 256 is triggered,thereby indicated to the operator that a blockage has occurred, andindicates specifically which gauge has detected a block.

FIG. 18 provides a basic example of how the gauge and sensor system nodecommunicate with the user interface 262. FIG. 18 presents a systemwherein a single CAN Bus 270 electrically wires a number of wired sensormodule assemblies 256 to a single wireless sensor module assembly 254.The lone wireless sensor module assembly 254 then wirelesslycommunicates the status of each sensor node module assembly 254, 256 tothe user interface 262 over a wireless connection 264. Updates that comefrom the user interface 262 are communicated wirelessly to the singlewireless sensor node module 254, which then updates the wired sensormodule assemblies 256 via a wired connection.

FIG. 19 shows a sensor wiring diagram for the alternative embodimentsensor module 254. The wiring architecture is identical to that of FIG.13, except that a WiFi module 268 is communicatively connected to theprocessor 81. This WiFi module allows the sensor module 254 towirelessly communicate with the user interface 262 as described above.WiFi provides electronic devices a means for exchanging data wirelessly,using radio waves, over a network. Other wireless communicationsnetworks could replace WiFi for similar results.

The microprocessor code base is responsible for processing data providedby the magnetic field sensors/Hall-Effect sensors as well as CAN bus andWiFi communication with other modules within the system. Themicroprocessor software is not based on a high level operating systembut will instead use a cyclic executive real-time scheduler to keepprecise timing of task execution with low overhead. Listed below are theprimary components of the microprocessor software and theirresponsibilities:

-   -   Bootloader: Provides ability to write an updated application to        the internal flash via CAN or wireless link and load the        application from flash and execute it.    -   Scheduler: Manages the execution and timing of all tasks.    -   ADC Processor: Manages the selection and digital conversion of        sensor columns and stores this raw data in RAM for processing.    -   WiFi Processor: Filters and processes incoming messages from the        WiFi module.    -   WiFi Transmission: Aggregates the blockage and flow rate status        of all CAN-connected Sensor Modules into messages; sends data to        the iPad app or another Wireless Module via WiFi.    -   Flow Metric Processor: Performs flow analysis calculations and        filtering based on raw sensor data.    -   CAN Message Processor: Filters and processes incoming messages        from the CAN bus.    -   Tasks: Schedulable items of the system that represent an        execution path of code that will be run for a defined interval.        -   ADC Sensor Sampling        -   Flow Analysis        -   CAN data packaging        -   WiFi Transmission        -   CAN Receiver Processing        -   WiFi Receiver Processing    -   Services: Implement logic that uses a component or driver to        produce a desired behavior.        -   Scheduler        -   Configuration    -   Components: Represent hardware devices external to the        microprocessor. Their implementations are specific to the part        number they are designed for and make use of one or more drivers        to interface with the microprocessor/peripherals.        -   WiFi Module        -   LED        -   Hall-Effect Sensors        -   Row Selection Switches        -   Analog Signal Amplifier    -   Drivers: Responsible for configuration and interface with the        microprocessor and peripherals. Their implementations are        specific to the hardware architecture and microprocessor family.        -   CAN        -   Serial Peripheral Interface Analog-to-Digital Converter            (SPIADC)        -   DAC        -   Timer        -   GPIO            V. Alternative Embodiment Flow Rate Sensor System 302

FIG. 20 presents an alternative embodiment flow rate monitoring system302 where the right side and left side of the liquid applicator arewired separately. A right side CAN bus 316 wires a number of wiredsensor module assemblies 306 to a single master wireless sensor assembly308. A left side CAN bus 318 wires a number of wired sensor moduleassemblies 306 to a single secondary wireless sensor module assembly310. The secondary wireless sensor module assembly 310 communicateswirelessly over a wireless connection 314 with the master wirelesssensor module assembly 308. Similarly to the system shown in FIG. 18,the master wireless sensor module assembly 308 then wirelesslycommunicates the status of each sensor node module assembly 306, 308,310 to the user interface 312 over a wireless connection 264. Updatesthat come from the user interface 312 are communicated wirelessly to themaster wireless sensor node module 308, which then updates the wiredsensor module assemblies 306 via a wired connection on the right sideCAN bus, and wirelessly updates the secondary wireless sensor moduleassembly 310, which then updates the wired sensor module assemblies 306via a wired connection on the left side CAN bus. It should be noted thatany CAN communication link could be a wireless communication link. CANlinks are utilized as a cost-saving measure.

The master wireless sensor node module 308 and secondary wireless sensornode module 310 would likewise include a WiFi module 268 for wirelesscommunication with each other and the user interface, as discussed inthe previous embodiment and shown at FIG. 19.

Above is discussed a situation where the flow rate through liquid linesand liquid monitoring gauges is lowered or blocked completely. It shouldbe pointed out that the system could also operate to alert a user oroperator when too much flow is traveling through the flow gauges and/orliquid lines. This may occur if a line is punctured or broken in someway. The level indicator ball 34 would be forced vertically upward, eventowards the top of the flow gauge 4. The user interface would alert theuser to this occurrence, allowing the user to remedy the problem.

VI. Alternative Embodiment “Self-Healing” Flow Rate Monitoring System402

FIG. 21 demonstrates the steps necessary for practicing a methodembodying yet another aspect of the present invention. In such anembodiment, a controller will be hooked up to a monitor, which saidcontroller could automatically adjust the flow rate in one or more ofthe flow gauge rows.

The method starts at step 404. The gauge levels are set or reset at 406,such that they will be in a desired or default position regarding flow.The flow begins at 408, with the liquid passing from the tank andthrough a flow meter before reaching the individual gauges and beingapplied to the field.

The system will monitor the flow through the flow meter at 410, and willcalculate the flow through each individual gauge at 412 based upon theheight of the magnetic ball 34 within the gauge 4. The system controllerwill monitor each gauge to see if one or more of the rows are out ofsynch at 414. This means that the system will determine if one or moreof the magnetic balls are out of position either compared with theremainder of the gauges or with a preset baseline.

If there are one or more rows out of synch, the particular row will becleared or the flow to that row will be altered such that all rows aresynched again at 416. If no row is out of synch or if the rows arere-synched, the user may select to quit at 418. If the user quits, themethod ends at 420. Otherwise the system returns to monitoring the flowrate of the flow meter in comparison with each of the gauges.

These steps allow the control system to “self-heal,” which ensures thatthe flow rate is equal to each row and through each gauge.Pre-determined mathematical calculations based upon the properties ofthe liquid being applied and the size of the liquid lines, flow meter,and other equipment may be used to determine the appropriate rate ofapplication. This can then be checked using the flow rate measurement ateach flow gauge. The user interface can also display the calculated flowrate numbers per liquid line, and using a sufficiently integrated userinterface, adjust the flow rates accordingly.

Alternatively, a controller could be connected to read each gaugeseparately, rather than the flow meter. This would serve the samefunction as above but would alter the calculations necessary. The systemwould simply compare each flow rate to the remainder of the gauges todetermine whether any discrepancies exist such that a blockage islikely. The system could simply increase flow to that particular row inthe event of low flow (or conversely reduce flow in the event ofabnormally high flow) or, as above, could notify the user that a row hasbecome blocked in the event of a complete blockage of flow.

It is to be understood that the invention can be embodied in variousforms, and is not to be limited to the examples discussed above. Therange of components and configurations which can be utilized in thepractice of the present invention is virtually unlimited.

Having thus described the invention, what is claimed as new and desiredto be secured by Letter Patent is:
 1. A flow rate monitoring system foruse with a liquid distribution system, the monitoring system comprising:a flow gauge including a housing through which liquid may flow, saidflow gauge connected to the liquid distribution system via a liquid feedline; an indicator located within said housing; a sensor assemblyincluding a sensor and affixed to an external face of said housing, saidsensor adapted for detecting a status of said flow gauge comprisingeither blocked or not blocked; a mobile computing device including aprocessor, data storage, and a graphical user interface, said mobilecomputing device communicating with said sensor assembly and configuredto produce a visual indication comprising either blocked or not blocked;said sensor adapted for detecting the vertical location of saidindicator within said housing; said processor configured to send andreceive signals from said sensor, thereby adjusting the settings of saidsensor and reporting the signals from said sensor to said userinterface; wherein the vertical location of said indicator relative tosaid housing is dependent upon the flow rate of liquid through saidhousing; a selectively adjustable liquid flow rate target for said flowgauge; said user interface adapted for indicating when the measured flowrate through said flow gauge diverges from said selectively adjustableliquid flow rate target; a flow controller adapted for receivingcommands from said user interface; and said user interface is furtherconfigured to respond to a change in said measured flow rate throughsaid flow gauge.